# Tag Info

## Hot answers tagged gravity

8

The basic concept here, that you instead of relying on having a large enough velocity that the Earth can not pull you back in time just have a low and constant velocity, and keeps thrusting to counteract gravity instead, is not flawed by default, given your assumptions Assuming that my fuel supply could last long enough, and I wasn't concerned about ...

7

The moon is gravitationally locked to the Earth. Because gravitational field depends on distance, the Earth's gravity does not affect the moon uniformly: the farthest side is not attracted as strongly as the closest side, these are tidal effects. This causes the heaviest side of the moon to face the earth, i.e. the moon is tidally locked to the earth. The ...

5

Newton's shell theorem proves that inside a gas giant, any layers that are further than you from the centre have a zero gravitational effect on you. So if you are inside a gas giant (and by some magic not dead) the only gravity comes from the layers that are closer to the centre. So the gravitational pull is always down. If fact, the pressure increases as ...

5

I worked out the math, it's pretty straight forward. If we take the Hill sphere, which is an estimate for the furthest possible orbit, and I'm going to just run the math on circular orbits. Eliptical orbits are harder to put in resonance anyway. the simple Hill Sphere formula. $3\frac{r^3}{a^3} = \frac{m}{M}$, where $a$ is the semi major axis planet to ...

5

It's a bit hard to answer this question as there are some ambiguities and certain parameters of the setup aren't defined, but I can try to give you a general idea. If we were to feel such gravitational waves, what would they feel like? I'll start here as we need to have some well established meaning for how we can feel a wave before calculating what ...

5

Straightforwardly no. For a start there are almost no free protons inside a white dwarf. They are all safely locked away in the nuclei of carbon and oxygen nuclei (which are bosonic). There are a few protons near the surface, but not in sufficient numbers to be degenerate. Let us assume though that you were able to build a hydrogen white dwarf that had ...

3

Proton degeneracy is not important, because its effect is much smaller -- much like nuclear particles in theory also are dictated by gravity, but the electromagnetic and nuclear forces are dominating, since they are much stronger. Proton degeneracy is weaker than electron degeneracy due to the far greater mass of the proton compared to the electron. The ...

3

Globular clusters formed whilst the gas of the proto Milky Way was still approximately spherically distributed. The gas forms a dissipative system that loses energy and collapses (within the first billion years) to a disk whilst conserving angular momentum. Formed stars and clusters are essentially collisionless so the halo stars continue to have a ...

3

No. That's not what a black hole is. A black hole is a vacuum solution to general relativity. In other words a black hole is just mass, without a "thing" left to be massive. The mass is collapsed to a singularity, and is surrounded by an event horizon. If you pass over the event horizon, every path you can take in will lead you to the singularity. In this ...

3

Escape velocity is how fast you must go in order to keep moving away indefinitely without additional thrust. If the Earth were the only major body in the system, and you moved away from it at 100 km/h for 1180 years, you'd be 6.9 AU away. Since Earth escape velocity at that distance is only 100 km/h, you could then stop the engine and coast to infinity. If ...

2

With the discovery of the Higgs Boson as the mass carrier, what is the possibility at the centre of a black hole being so dense and gravity so infinite that the structure of a proton or neutron are ripped apart into their fundamental elements by these extreme energies that Higgs Bosons are massed together at the centre, The center of a black hole ...

2

Velocity is a vector quantity with both a magnitude and direction. The magnitude of velocity is speed. During the Earth's nearly circular orbit, the speed changes little, but the direction of motion changes, and this change of direction is the acceleration. The Earth is always accelerating towards the Sun. When we speak of velocity one should mention the ...

2

Something to remember is that the total mass of asteroids in the asteroid belt is tiny compared to the masses of the planets. Ceres, the largest body in the asteroid belt by a wide margin, is only 0.00015 times the mass of Earth, Ceres itself accounts for about a third the belt's mass: Asteroid belt facts from ScienceDaily I haven't been able to find any ...

2

When a body spins around another body due to gravity and maintains a consistent orbit, we can know clearly two things about the body: 1. The speed of the orbit 2. The average radius of the orbit Think about it. The Moon spins around the Earth due to gravity of the Earth. Right? And it's orbit always stays the same(when averaged). For it to stay in this ...

2

Nothing in your description sounds wildly implausible. I'll just go through and extend some of your properties to make sure they make sense though. The planet has three times Earth's mass I'll assume that your new planet is Earth-like in composition and density. That implies that it's radius should be about $R_p \approx 1.4 \: R_\oplus$. Let's put that ...

2

I see no reason why this wouldn't work. The innermost Galilean moons are in a 1:2:4 resonance so it's clearly a stable orbital configuration. They could all be tidally locked if you want, but the planet itself can't be tidally locked with all of them. If the planet were tidally locked it would likely be locked with the innermost moon. Also of note, the ...

1

Firstly the skymap for the GW150914 event covers some 600 square degrees, of which the Large Magellanic cloud is only a small fraction of that, and furthermore the estimated distance to this merger is around 400Mpc, orders of magnitude larger than the distance to the LMC (~50kpc) [source]. So dont assume this is where it came from because the error boxes are ...

1

Short answer Three detectors would improve the ability to pinpoint the direction of the gravitational waves drastically. Long answer Finding the direction of the source of a gravitational wave, as with most things in science, is harder than it might initially seem. I'd like to point out that the process used in determining direction is not precisely a ...

1

You and your phone will be destroyed before you get to the black hole, but If we pretend that you and your phone can survive being in the vicinity of a black hole ... And let's suppose this is a regular black hole of about 5 to 10 solar masses, and you are falling in, you are not trying to orbit it. As you fall towards the black hole, at first there is no ...

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